1. Field of the Invention
The present invention relates to a new switch architecture that is independent of the type of media, where the media is the physical connections and protocols that allow data to be received and processed. More specifically, the architecture allows for a switch configuration to be adapted to the needs of the switching environment, especially if the switching environment is directed to mixed types of media.
2. Description of Related Art
A switch is defined as a network component that receives incoming data, stores the data temporarily, and sends the incoming data (either untouched or maybe after some modifications) to another port. The switching is accomplished by determining a destination address from the incoming data and sending the data to a port or multiple ports associated with the destination address. The use of switches is essential in handling the flow of data in high speed networks.
A switch for networking applications is generally dedicated to handle a particular Media type and Networking technology. The Architecture of such switch, being closely coupled to a Media type, is often difficult to adapt to future Media types and emerging packet switching technologies. As an example, the carrier-sense multiple access with collision detection (CSMA/CD) Ethernet networking switches have their architecture based on Std 802.3 defined Media Access Controllers (MAC) and Physical layer (PHY) subsystem as their building blocks. The current Std 802.3 based Ethernet switches are tightly integrated with the MAC layer and to some extent depend upon the PHY for link status. The current network switches would need to be re-designed to adapt to other networking technologies or different media interfaces.
In addition, because current switch architectures are media-centric, i.e. centered on the type of media for which they switch data, this aspect often limits the structure of the switches. Thus, a switch developed to provide switching of Ethernet packets may not be able to switch data that a cable set type box would receive and both switches could be configured quite differently because of the media types that they handle. Because of this, the media type determines the switch architecture to a large degree. Many times, the sections of the switch that determine the MAC, address resolution and content aware filtering logic are integrated in one Block to provide std. 802.3 compliant Ethernet Switching.
The architectures associated with specific media types do have the advantages of being highly integrated and highly optimized as a Single Chip solution for that media type. They do, however, have several limitations in terms of flexibility. Specifically, they only support one Media type (for example: std. 802.3, Ethernet-II switching and routing), and they require special external chips or converter logic to interface to other Media types like Wireless, ADSL/VDSL, Sonet etc, and many times they require new Silicon implementations to support higher or lower port density.
The prior art switches also prevent a provider of the switches from meeting the specific needs of the users of those switches. As an example, consider a specific switch on a chip that provides for 34 fast Ethernet ports and 2 Gigabit ports. One customer for that chip may want to have 40 fast Ethernet ports, another may want to have the capacity of 4 Gig ports and a third may wish to have just 24 fast Ethernet ports. Because the chip architecture is predetermined, the first customer would need two of the specific chips so configured to meet their requirements. The second customer would also require two specific switches to meet the need for 4 Gig ports, while the third would only require a single switch, but the chip would be under-utilized. In each case, the customer must purchase capacity for which it doesn't need and it makes it more difficult for a producer to meet the specific demands of the consumer. In addition, as discussed above, if the customers want to use the switches using “mixed media types,” or allow for future use with new media types, they cannot use the purchased switches in those capacities. As an example, consider a customer who has 802.11 based LAN network, Std 802.3 based LAN Network, Home appliance Network based on some industry standard. If the customer wants to switch traffic between these three different Media types, the current architectures require bridging between all the three LAN networks using different set of ASIC solutions.
Thus there is a need to a switch architecture that allows for the number and type of ports to be customized without underutilizing the processing abilities of the switch. Additionally, there is also a need for a switch architecture that allows for expandability and continued customization after the sale of the initial switch configuration.